Gravitational force pulls on each unit mass with a constant force resulting in a constant acceleration (an increase in speed of about 10 metres per second every second). ... This is said to be the 'weight' of the object (i.e. the downward force it exerts because gravitational force is acting on it).
Xerophytes are plants that have adapted to arid climates. They have evolutionary developed adaptations to reduce the rate of transpiration so as to conserve water.
Among the adaptations include; thick cuticle, small, thick leaves, reducing the surface area relative to the volume of the leaf, etc.
Additionally, they use CAM pathway as an alternative photosynthetic pathway to minimize water loss.